This invention relates to a connector for use in an electric endoscope, especially for connecting a main body with a scope part therebetween.
In a conventional endoscope-connector, a rotating handle (that is, a bayonet collar) is in the shape of a cylinder and has a cam. The bayonet collar is coaxially disposed through the bearing portions around an outer surface of a housing accommodating a plurality of connector terminals. When receiving the bayonet collar with the bearing portions, since the length along the axial direction of the bayonet collar is relatively longer, bearing portions are disposed on opposed ends of the bayonet collar, respectively, so that the opposed ends of the bayonet collar are received by the bearing portions. In this type of connector, in order to prevent looseness of connection between the connector and the main body and to improve the operation feeling, the bayonet collar is provided with an appropriate friction.
To supply the friction to the bayonet collar, a friction board which is made of wool puff, synthetic leather and the like is put into a space between the bayonet collar and the housing and between each bearing portion. Alternatively, a leaf spring which is made of metal or resin is added to supply a side pressure to the bayonet collar from an inside thereof.
However, the method of using the friction board is difficult to have a stable friction torque because of subtle different sizes of the friction board. The method of using the leaf spring has an extremely smaller friction coefficient at a contact point between the bayonet collar and the bearing portions in comparison with the method of using the friction board. Therefore, it is necessary for the method using the leaf spring to supply a larger load to the contact point to have a heavy friction torque. As a result, the leaf spring is subjected to a heavy abrasion of a resin of the contact point.
Conventionally, when washing or disinfecting the scope portion provided with this type of connector, a water proof cap is fitted to the end opening of the connector to avoid the wash water or disinfectant to inflow into the connector from the end opening thereof.
However, It is difficult to quickly mount or dismount the cap on or from the connector, because the water proof cap is screwed into the connector along a thread provided on a peripheral surface of the connector.
Therefore, in the case of the electric endoscope apparatus comprising the main body and the scope portion which are connected to each other by using this type of conventional connector, a need of an abrasion-proof would occur or a stable friction torque to the bayonet collar would not secured. Furthermore, because of the aforesaid problem, a great deal of time is lost when preparing for starting an examination or when washing and disinfecting. Especially, it is difficult to deal with the time loss when desired to quickly wash the scope portion in a short clinical time.